Phobos-Grunt image taken from ground, on Nov. 29, 2011 by amateur astronomer Ralf Vandebergh from The Netherlands.
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While amateur astrophotographers have been tracking the Phobos-Grunt spacecraft in its orbit around Earth, ESA has decided to curtail operations to try to make further contact with the ailing craft. “Efforts in the past week to send commands to and receive data from the Russian Mars mission via ESA ground stations have not succeeded; no response has been seen from the satellite,” ESA reported in a press release. They made this decisionafter consultation with mission managers in Russia, but teams will remain available to assist if there is any change in the situation.
ESA teams from a tracking station at Perth, Australia had established contact with the Russian spacecraft on November 22 which was the first signal received on Earth since the mission to Mars’ moon was launched on November 8, 2011. Since then, however, weren’t able to maintain contact.
Above, Ralf Vandebergh from the The Netherlands has imaged the spacecraft in orbit and this graphic compares the images to the components on pictures of the spacecraft.
Below, and a video from another astrophotographer in The Netherlands tracks the spacecraft during a night pass, and another image from Vandebergh shows color differences between the solar panels and the main body,
Marco Langbroek captured this footage from near Leiden, The Netherlands on Nov. 28, 2011. See more at his website.
Noticable color differences between the main body and solar panels of Phobos-Grunt. Credit: Ralf Vandebergh
Maspalomas station hosts a 15-metre antenna with reception in S- and X-Band and transmission in S-band. It is located on the campus of the Instituto Nacional de Tecnica Aerospacial (INTA), in the southern part of the Canary Islands' Gran Canaria, at Montaña Blanca.Credit: ESA
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Editor’s note: Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the Phobos-Grunt spacecraft, provides an update on the mission for Universe Today.
As part of an effort to improve communication with the Russian Space Agency’s Phobos-Grunt spacecraft, modifications are being made to a 15-meter dish antenna at Maspalomas station. Located in the Canary Islands off the Atlantic coast of North Africa, the station provides tracking, telemetry, and other functions in support of the European Space Operations Centre (ESOC) of the European Space Agency (ESA).
Last week, ESA succeeded in communicating with Phobos-Grunt on two successive days after a feedhorn antenna was added to an antenna near Perth, Australia similar to the facility in Maspalomas. Although this enabled the downloading of spacecraft telemetry, attempts later in the week to make renewed contact failed. After no attempts were made over the weekend, commands aimed at getting the spacecraft to boost its orbit were sent yesterday, also from Perth, but tracking this morning revealed that the commands had not been executed.
Launched November 9 from the Baikonur Cosmodrome, in Kazakhstan, Grunt is an unpiloted science probe built to travel to Phobos, the larger of Mars’ two small moons. On board is a science payload consisting of numerous instruments designed to elucidate the structure and origin of Phobos, the composition of its surface material, and possibly dust from Mars that may be present as well. A Chinese probe called Yinhuo-1 is to be delivered into orbit around Mars, while the rest of the payload is to land on the Phobosian surface. Some time after landing, a 200 gram sample of the surface is to be deposited into a capsule which then will launch for a journey back to Earth. Also traveling in the return capsule is the Planetary Society’s Living Interplanetary Flight Experiment (LIFE), which I helped to design. As with the Phobosian surface sample, the LIFE experiment will be valuable scientifically, only if the return capsule can be returned to Earth.
Although Phobos-Grunt was delivered into space nearly three weeks ago by a Zenit 2 rocket launch that appeared flawless, an upper stage rocket known as Fregat failed to ignite. This left the spacecraft in a low Earth orbit that improved as a result of the automated maneuvering, but that will decay by mid-January if the altitude is not boosted more significantly. Because a low orbit requires a spacecraft to move more swiftly with respect to the ground, communication is extremely limited due both to time and geometry. By allowing Maspalomas to operate similarly to Perth, but from its different location, both geometric and time factors affecting communication will be improved. Should this result in the spacecraft executing commands to climb to a higher orbit, further communication and diagnosis of spacecraft systems then would become much easier.
It hasn’t been a great year for Roscosmos, the Russian Federal Space Agency. In the last twelve months, it has lost four major missions on top of the aerospace industry’s failure to produce its planned number of spacecraft.
For the most part, lost missions conjure up feelings of despair for the spacecraft from a scientific or exploration perspective – what does the silent satellite or failed launch mean for the agency’s immediate and overall goals? But there’s another side to lost missions that are less common. What does a lost mission or failed launch mean for the people responsible? All four missions Roscosmos has lost in the last year have been substantial. In December 2010, a Proton-M booster failed to put three Glonass-M satellites in orbit. These were meant to enhance Russia’s Global Navigation Satellite System, the Russian counterpart to America’s GPS system, and just recently, Russia successfully launched replacements.
In February, a Rokot booster carrying the Geo-IK-2 satellite ended in failure. The satellite was designed to build on Russia’s geodesic research. Acting as a precise reference point, it would help scientists take accurate measurements of the Earth’s shape and the properties of its gravitational field and support such fields as cartography, missile guidance, study of tectonic plate movements, ocean tides, and ice conditions.
A schematic showing the loss of theProgress M-12 expendable spacecraft. Credit: RIA Novosti.
The loss of these missions was doubtless devastating for the teams who designed them, but the After the loss of Geo-IK-2, a number of senior space industry officials were fired and Roscosmos’s chief, Anatoly Perminov, was forced to resign.
In August, another Proton-M rocket failed to launch an Ekspress-AM4. The communications satellite was designed to provide digital television and secure government communications throughout the Russian Federation extending far into Siberia and the Far East.
This failure prompted further disciplinary action. A Russian State Commission of inquiry was established to determine the reasons for the failure. The International Launch Services (ILS), a joint US-Russian venture with exclusive rights to launch commercial payload from the Baikonur Cosmodrome in Kazakhstan, formed its own Failure Review Oversight Board to review Roscosmos‘ final internal report. The final verdict was both missions were lost due to negligence.
Things didn’t get better for the Russian Space Agency. Only a week after the loss of Eskpress-AM4, A Soyuz-U booster failed. Its cargo, the Progress M-12 expendable cargo spacecraft, never reached the crew waiting for its contents aboard the International Space Station.
Now, it looks like further harsh disciplinary action might befall the scientists and engineers behind the failed Phobos-Grunt. Designed to land on Mars’ larger moon and return a soil sample, the spacecraft got stuck in Earth orbit in November. Russian President Dmitry Medvedev has suggested that those responsible for the failure need to be punished. They could he fined, he said. He even went so far as to suggest criminal prosecution. The threat might be directed at Lavochkin, the company that built Phobos-Grunt.
Russian President Dmitry Medvedev. Credit: RIA Novosti
It’s possible Medvedev is protecting the Russian people who, like Americans, foot the bill of their nation’s space program. But he might not be. The failures do, after all, deal a serious blow to Russia’s technological pride and standing as a power in space.
“I am not suggesting putting them up against the wall like under Josef Vissarionovich (Stalin), but seriously punish either financially or, if the fault is obvious, it could be a disciplinary or even criminal punishment,” Medvedev said.
Surprisingly, or perhaps not, Roscosmos isn’t the only Russian industry to be target by Medvedev’s calls for disciplinary action. Similar calls have been made for disciplinary action after carelessness, corruption, and problems within Russia’s infrastructure, such as a riverboat sinking in July that killed 122. The difference is that no one dies when an unmanned spacecraft fails to complete its mission.
A mosaic of nine oblique views from the MESSENGER spacecraft of Mercury's limb, looking towards the horizon. Click for larger, more amazing view. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
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Wow — just wow! Here’s a unique, jaw-dropping, and beautiful look at Mercury from the MESSENGER spacecraft, in a mosaic created from nine images taken by the Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS). The camera took a “sideways” or oblique view of Mercury’s limb, looking towards the horizon, providing a distinctive look at the rough terrain, ridges, craters and scarps of the Van Eyck Formation region, adjacent to the Caloris basin. Combining the images for a larger view not only provides a “you are there” feel, but it provides the science team with new ways to study Mercury’s geology.
Make sure you click on the image for a larger, even more amazing view. You can compare this image with a “straight-down” look of the same region, below.
Correlation of features between the limb mosaic and an overhead view. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Looking at any landscape in from different angles has a major impact on how terrain location and feature orientation is perceived, the MESSENGER science team explained in a detailed description of how this image was made. While single images that focus on one feature are wonderful for in-depth explorations, combining images together in a mosaic studying can provide regional or even global perspective. These mosaics are particularly important for understanding the geological context of a particular feature and for exploring Mercury’s geologic history.
The Van Eyck region was formed by ejecta from the Caloris basin. Visible in the overhead view are “ghost craters” which are impact craters that were later buried by the voluminous volcanic lavas that form the plains in this part of Mercury. What appear as rough terrain and ridges in the oblique limb view show up as lineated, distinctive features from overhead. Both views provide clues to scientists about the processes or environment that the features formed.
The ejecta blanket of Caloris basin is to the lower left of the overhead-view.
The limb mosaic is just 9 of 75,000 images the NAC has taken and will continue to take during MESSENGER’s primary mission, which goes through March of 2012. These images were taken in June of 2011, and the mosaic was released today by the imaging team.
The Mars Science Laboratory is now on an 8.5 month trip to Mars! Watch the successful launch above, and our on-site team of Ken Kremer, Alan Walters, David Gonazales and Jason Rhian will provide all the launch details and more in subsequent, fact- and photo-filled articles.
Getting the Mars Science Laboratory to the Red Planet isn’t as easy as just strapping the rover on an Atlas V rocket and blasting it in the general direction of Mars. Spacecraft navigation is a very precise and constant science, and in simplest terms, it entails determining where the spacecraft is at all times and keeping it on course to the desired destination.
And, says MSL navigation team chief Tomas Martin-Mur, the only way to accurately get the Curiosity rover to Mars is for the spacecraft to constantly be looking in the rearview mirror at Earth.
“What we do is ‘drive’ the spacecraft using data from the Deep Space Network,” Martin–Mur told Universe Today. “If you think about it, we never see Mars. We don’t have an optical navigation camera or any other instruments to be able to see or sense Mars. We are heading to Mars, all the while looking back to Earth, and with measurements from the Earth we are able to get to Mars with a very high accuracy.”
This high accuracy is very important because MSL is using a new entry, descent and landing guidance system which will allow the spacecraft to land more precisely than any previous landers or rovers.
“It is very challenging, and even though it is something similar to what we have done before with the Mars Exploration Rover (MER) mission, this time it will be done at an even higher level of precision,” Martin-Mur said. “That allows us to get to a very exciting place, Gale Crater.”
The Goldstone Antenna, part of the Deep Space Network. Image Credit: JPL
On Earth, we constantly can find exactly where we are with GPS – which is on our cell phones and navigation equipment. But there is no GPS at Mars, so the only way the rover will be able to head to –and through — a precise point in the Red Planet’s atmosphere is for the navigation team to know exactly where the spacecraft is and for them to keep telling the spacecraft exactly where it is. They use the Deep Space Network (DSN) for those determinations from launch, all the way to Mars.
The Deep Space Network consists of a network of extremely sensitive deep space communications antennas at three locations: Goldstone, California; Madrid, Spain; and Canberra, Australia. The strategic placement approximately 120 degrees apart on Earth’s surface allows constant observation of spacecraft as the Earth rotates.
But of course, it’s not as easy as just getting the rocket from Point A to Point B since Earth and Mars are not fixed positions in space. Navigators must meet the challenges of calculating the exact speeds and orientations of a rotating Earth, a rotating Mars, as well as a moving, spinning spacecraft, while all are simultaneously traveling in their own orbits around the Sun.
There are other factors like solar radiation pressure and thruster firings that all have to be precisely calculated.
This artist's concept depicts the rover Curiosity, of NASA's Mars Science Laboratory mission, as it uses its Chemistry and Camera (ChemCam) instrument to investigate the composition of a rock surface. Credit: NASA/JPL
Martin-Mur said even though MSL is a much bigger rover with a bigger spacecraft and backshell than the MER mission, the navigation tools and calculations aren’t much different. And in some ways, navigating MSL might be easier.
“The Atlas V vehicle provides a much more precise launching and can put us in a more precise path than the MER, which used a Delta II,’ Martin-Mur said. “This allows us to use less propellant, proportionally per pound, to get to Mars than the MER rovers did.”
The MER rovers and spacecraft weighed about 1 ton, while MSL weighs almost 4 tons. MSL is allotted 70 kg of propellant for the cruise stage, while the MER rovers each used about 42 kg of propellant.
Interestingly, for the MSL spacecraft to descend through Mars’ atmosphere and land, the spacecraft will use about 400 kg of propellant.
Additionally, Martin-Mur said more precise planetary ephemeris and Very Long Baseline Interferometry measurements are available, enabling the navigation to be able to deliver the spacecraft to the right place in the atmospheric entry interface, so the vehicle finds itself in the range of parameters that it has been designed to operate.
Navigation at Launch
It all starts with years of preparations and calculations by the navigation team, which must calculate all the possible trajectories to Mars depending on exactly when the Atlas V rocket launches with MSL aboard.
In some cases there are literally thousands of launch opportunities and all the possible trajectories must be calculated precisely. The Juno mission, for example, had two-hour daily launch windows with 3,300 possible launch opportunities. For MSL the daily launch windows contain liftoff opportunities in 5 minutes increments. Across the 24 day launch period the team has calculated 489 different trajectories for all the possible launch opportunities.
But ultimately, they will end up using only one.
“This is not something you do on the fly – you prepare all this well in advance so you have time to sit back and assess it and check it,” said another member of the MSL navigation team, Neil Mottinger, who has worked at the Jet Propulsion Laboratory since 1967. He’s worked on navigation for many missions like Mariner, Voyager, the MER, and several international missions.
“The initial function of navigation at launch is to determine the actual spacecraft trajectory well enough so the spacecraft signal will be well within the beam-width of the DSN antennae,” Mottinger told Universe Today.
The Mars Science Laboratory will separate from the rocket that boosted it toward Mars at about 44 minutes after launch, with the navigator’s tracking the spacecraft’s every move.
Mottinger added that without the DSN’s communication capabilities, there are no planetary missions. “The Navigation team does whatever it can to make sure there aren’t any gaps in communication,” he said. “It’s crunch time during the first 6-8 hours after launch to be able to determine the exact position of the spacecraft.”
From the recent problems with the Phobos-Grunt mission, it is evident how difficult it is to track and communicate with a just-launched spacecraft.
The MSL Entry, Descent and Landing Instrument (the black box in the middle left of the photo) is scheduled to launch as part of the Mars Science Laboratory mission. Credit: NASA
Mid-course Corrections
Again, the navigation team has modeled and calculated all the maneuvers and thruster burns for the mission. Once MSL is on its way to Mars, the navigation team will revisit all their models and design the maneuvers to take the spacecraft to the right entry interface at Mars.
“We’ll keep doing orbit determination and re-designing the maneuvers for the spacecraft,” said Martin-Mur. “MSL has 1 lb thrusters – the same size as the MER spacecraft — but our spacecraft is almost four times heavier so the maneuvers we do take a long time – some will take hours.”
For interplanetary navigation, the engineers use distant quasars as landmarks in space for reference of where the spacecraft is. Quasars are incredibly bright, but are at such colossal distances that they don’t move in the sky like nearer background stars do. Martin-Mur provided a list of nearly 100 different quasars that could be used for this purpose, depending on where the spacecraft is.
“It is interesting,” Martin-Mur mused, “with quasars we are using something that is billions of light years away from us, from the very early universe, which are so old that they might not even be there anymore. It is really cool that we are using an object that currently may not exist anymore, but using them for very precise navigation.”
The navigation team also needs to model the solar radiation pressure – the effect the Sun’s radiation has on the spacecraft.
“We know very well, thanks to our friends from the Solar Systems Dynamics group, where Mars is going to be and where the Earth and Sun are,” said Martin-Mur. “But since this spacecraft has not been in space before, what is not known precisely is how solar radiation pressure will affect the surface properties of the spacecraft, and how it will perturb the spacecraft. If we don’t have a good model for that, we could be hundreds of kilometers off as the spacecraft goes from Earth to Mars.”
Powered Descent, Sky Crane & Flyaway for MSL. Credit: NASA/JPL
Arriving at Mars
As the spacecraft approaches Mars, it is very important to know precisely where the spacecraft is. “We need to target the spacecraft to the right entry point,” said Martin-Mur, “and tell the spacecraft where it will enter, so it will be able to find its way to the landing site.”
The MSL Entry Descent and Landing Instrumentation, or MEDLI, will stream information back to Earth as the probe enters the atmosphere, letting the navigators — and the science team – know precisely where the rover has landed.
Only then will the navigation team be able — maybe — to breathe a sigh of relief.
Final preparations for launching Phobos-Grunt in early November 2011. Credit: Roscosmos
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Editor’s note: Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the Phobos-Grunt spacecraft, provides an update on the mission for Universe Today.
In an exciting development in the ongoing story of the Phobos-Grunt mission, a tracking station at Perth, Australia established contact with the Russian spacecraft on November 22 at 20:25 UT. This was the first signal received on Earth since the mission to Mars’ moon was launched on November 8, 2011.
Teams from ESA, who made the initial contact, are now working closely with engineers in Russia to determine how best to maintain communications with the spacecraft. As controllers begin the task of figuring out how to use this achievement to enable sending the spacecraft new commands, discussion is ongoing on whether the launch window will still be open for the craft to complete the mission.
The hopes are now is that at the very least engineers can prevent the spacecraft from plummeting back to Earth – and with guarded optimism that the mission could proceed in some manner.
Before contact was made, some reports said that if contact was made by November 24, the mission could proceed as planned, while other experts were saying that the launch window to complete the sample return mission closed on November 21.
But yet, a mission leaving from Earth orbit well into December might still succeed.
Engineers tuck Phobos-Grunt into the rocket fairing. Credit: Roscosmos
Built to travel to Phobos, the larger of Mars’ two moons, the centerpiece of the unmanned spacecraft is a small capsule in which 200 grams of regolith (surface material consisting of dust and crushed rock) is to make a return flight to Earth. To launch the capsule on a flight that would return it to Earth in 2014, the spacecraft was scheduled to land on Phobos in February 2013 after entering orbit around Mars in October 2012.
A launch window is a period during which travel from one celestial body to another is possible, given a spacecraft’s propulsion capabilities and the alignment of the celestial bodies as they move through space. In the future, advanced propulsion technologies could allow for trips between Earth and Mars to depart at any time, but for now spacecraft must wait for the optimal moment. For trajectories from Earth to Mars, launch windows occur roughly every 26 months, as do launch windows for inbound flights to Earth from Mars.
The launch window for an Earth-to-Mars trajectory actually would allow Grunt to reach Mars and Phobos, if the spacecraft is readied for departure within two or three weeks from today. In such a case, however, the collection of regolith on the Phobosian surface would take place after that window has closed for the capsule to launch back to Earth. This is why people are saying that the window for Phobos-Grunt will close this Thursday.
But, as stated earlier, the window could still be open through mid-December. To see why, let’s take a glimpse of the Grunt’s science payload and other components . Sitting in front of what the Russian Space Agency is calling the sustainer engine, whose job is to propel the spacecraft from Earth to Mars, is a 110 kilogram probe called Yinhuo-1. China’s first Mars probe, Yinhuo-1 is to orbit the Red Planet for two years, performing various scientific studies. Moving forward from Yinhuo-1, brings us to the interplanetary module, Grunt’s descent stage.
Costing 5 billion rubles, or about 160 million US dollars, the interplanetary module is equipped with a descent engine and legs for landing on the Martian moon, machinery for scooping the regolith sample, and about 50 kilograms of extremely advanced scientific equipment whose value to the mission does not depend on whether the regolith sample makes it back to Earth.
Finally, there is the ascent stage and the return capsule that will lift off with it for the flight to Earth. In addition to accommodating the regolith that will be deposited inside, the capsule holds the Planetary Society’s LIFE biomodule, a study of the effects of the interplanetary space environment on organisms during a long-term voyage through space.
Before and after the departure of the return capsule, the instruments of the interplanetary module will be at work, performing celestial measurements, studying solar wind, and conducting geophysical studies -experiments whose results will help planetary scientists to understand the origin of our Solar System. The science package also will perform elemental, chemical, mineralogical, and thermal analysis of the regolith, look for traces of gases from Mars, and search for organic matter, the stuff of life.
ESA's Perth station, which made contact with the Phobos-Grunt spacecraft, is located 20 kilometres north of Perth, Australia. Credit: ESA
If Grunt were to make a one-way trip to Phobos, all of these studies could be performed, while Yinghuo-1 could be deployed around Mars, as is supposed to happen during a round-trip voyage. If it were determined that the capsule really had no chance of making it from Phobos back to Earth, the capsule might even be jettisoned in high Earth orbit before the sustainer stage completes the final burn to escape Earth’s gravitational pull. This might return the LIFE biomodule to Earth after a long trajectory through deep space that would satisfy the objectives of the experiment. Then, we could recover our biomodule and study the organisms as planned.
On the other hand, controllers might consider sending the return capsule to Phobos despite the closure of the launch window for a return flight. After landing on the Martian moon atop the interplanetary module, the ascent stage need only wait until the next launch window opens 26 months later for arrival on Earth in 2016.
The contact now made with the spacecraft may open up even more possibilities for saving the mission. ESA said in a press release that the signals sent to Phoboos-Grunt commanded the spacecraft’s transmitter to switch on, sending a signal down to the station’s 15 m dish antenna.
Data received from Phobos-Grunt were then transmitted from Perth to Russian mission controllers via ESA’s Space Operations Centre, Darmstadt, Germany, for analysis.
Additional communication slots are available on November 23 at 20:21–20:28 GMT and 21:53–22:03 GMT, and ESA teams are working closely with Russian controllers to determine how best to maintain communication with their spacecraft.
A region within Endeavour Crater on Mars that has been named 'Turkey Haven,' Credit: NASA/JPL, colorization by Stu Atkinson.
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What does a Mars Rover do for the Thanksgiving holiday? While one rover will be sitting on the launchpad, preparing to head to the Red Planet (MSL/ Curiosity) the Opportunity rover has now trekked to an enticing outcrop near the summit of Cape York on the rim of Endeavour Crater. This summit or ridge has been named “Turkey Haven” by the MER science team, as this is where Oppy will conduct scientific studies over the four-day-long US holiday. The image above was taken a few days ago, showing the Turkey Haven ridge. Our pal Stu Atkinson has provided a beautiful color rendering, and you can see all the rocks that the rover will be looking at more closely with its suite of instruments and cameras. You can see more images of this area, including 3-D versions on Stu’s site, Road to Endeavour.
Oppy is now sitting among these rocks studying the outcrop region seen on the left.
And there’s other enticing regions ahead to study as well.
An usual dagger-shaped feature along the rim of Endeavour Crater, as seen by the HiRISE camera on the Mars Reconnaissance Orbiter. Credit: NASA/JPL
A dagger-shaped gorge or geological fault, as seen from above by the Mars Reconnaissance Orbiter may well be a future destination, but likely after Oppy finds another haven – a winter haven – a good place and location for soaking up as much sunshine as possible for the upcoming long winter on Mars.
The rock outrcopping called 'Homestake," with part of the Opportunity rover visible. Credit: NASA/JPL. Colorization courtesy Stu Atkinson.
But behind Oppy was a most intriguing light-colored rock outcropping – this one was named “Homestake.” The rover spent several days studying the rock – even doing what could be termed a cruel drive-by (or driver-over). You can see in this image below, how Oppy really created havoc and a mess with her studies of this region:
A before-and-after montage of the Homestake outcropping, before and after the Opportunity rover drover over the rocks. Credit: NASA/JPL. Color and montage by Stu Atkinson
…leading Stu Atkinson to create this:
A crime scene on Mars? Credit: NASA/JPL, liberties taken by Stu Atkinson.
But seriously, many Mars rover fans are anxiously waiting to hear from the science team about what they found during Oppy’s close-up studies of this unusual rock outcropping.
Opportunity’s odometer reading is now over 21.33 miles (34,328.09 meters, or 34.33 kilometers).
Configuration of the Phobos-Grunt spacecraft. Credit: NPO Lavochkin
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Editor’s note: Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the Phobos-Grunt spacecraft, provides an update for Universe Today on the likelihood of saving the mission.
Although the launch window for a round-trip to Mars closed yesterday (November 21, 2011) with Russia’s Phobos-Grunt probe still circling in low Earth orbit, a one-way flight to the Red Planet will be possible for another few weeks. As Russian engineers frantically try to contact the silent probe, scientists from the Yinghuo-1 and LIFE experiments are holding out hope that they could still complete their missions, or a perhaps even a modified version of their experiments.
Launched November 9 to collect a surface sample from the larger of Mars’ two moons, Phobos, the 13-ton spacecraft was to be boosted from its initial parking orbit low in Earth’s skies within hours after reaching space, when the engine of its Fregat upper stage failed to ignite. Thought to have reverted to safe mode, Phobos-Grunt has been flying straight and periodically adjusting her orbit using small thruster engines. While this maneuvering has extended the amount of time that the probe can remain in space before reentering Earth’s atmosphere, ground controllers have been struggling to establish a communication link.
The Phobos-Grunt mission profile. Credit: Roscosmos
Had the malfunction occurred just one step further into the flight –after a first burn of the Fregat was to raise the apogee (the highest point) of the spacecraft’s orbit to an altitude of about 4,170 kilometers– the timing and geometry between Earth-bound transmitters and the spacecrafts antennae would have made signaling the craft a straight forward task. But with Grunt orbiting much lower (thus moving much faster with respect to the ground), and with an antenna that could receive the signal obstructed partially by a fuel tank that was to be jettisoned after the first Fregat burn, controllers have only a couple of minutes at a time to attempt communication. Since the spacecraft was not designed for this scenario, getting her attention may be depend on prospect of getting the signals toward her at some unlikely angle. In other words, restoring control over Phobos-Grunt may be a matter of luck.
But if luck is a factor in recovering the spacecraft, then the extension of her expected time in orbit due to thruster firings may prove helpful. The more time that controllers have to attempt contact, the better the chances that they’ll get lucky at some point before the craft reenters the atmosphere.
If this should happen, however, where should the probe travel? As of yesterday, it no longer will be able to go Mars, land on the surface of Phobos, scoop a 200 gram sample into the specially-designed return capsule, and still have a window for the capsule to be launched on a trajectory back to Earth. Last week, a lunar mission was discussed as a possibility.
But as a story released yesterday by the Russian news service Ria Novosti notes, the launch window to Mars for a craft that does not need to return to Earth remains open. In the case of NASA’s Mars Science Laboratory with its rover “Curiosity,” for example, the launch window to Mars is open until December 18.
This means that –if communication with Grunt is established– the Phobos-Grunt could be launched on a trajectory to Mars. This would not support the objective of return a sample from the Phobosian surface. However, since China’s Yinghuo-1 probe is piggybacked on the spacecraft for delivery into orbit around Mars, its mission at least would not be affected by the lack of a return flight.
The Planetary Society’s Living Interplanetary Flight Experiment (LIFE) capsule, on board the Phobos-Grunt spacecraft. Credit:The Planetary Society
Then, there is the Planetary Society’s Phobos-LIFE. The objective of this project is to study the effects of the interplanetary environment on various organisms during a long duration flight in space beyond the Van Allen Radiation Belts, which protect organisms in low Earth orbit from some of the most powerful components of space radiation. If the biomodule containing the LIFE organisms travels one way to Mars, it will not help the experiment. But it may be possible to jettison the return capsule when the spacecraft is in a high orbit around Earth, before the final burn sending it toward Mars has been completed. If this happens, the return capsule –which would not be needed anyway for a one-way Mars mission– might be set on a trajectory that takes it beyond the Van Allen belts for many months, or longer, but that eventually takes it back to Earth. If so –and as usual, I emphasize the “IF” – the capsule could make the reentry and landing that it was designed to do, we could recover our biomodule and study the organisms as planned.
The Phobos-Grunt mission profile. Credit: Roscosmos
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Editor’s note: Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the Phobos-Grunt spacecraft, provides an update for Universe Today on the likelihood of saving the mission.
If communication with Russia’s troubled Phobos-Grunt is not established by November 21, the window for a trajectory to the Martian moon Phobos, will close, experts say. But this would not mean that the spacecraft could not travel to a different destination. In a statement published earlier today by the news and information agency Ria Novosti, Russian space expert Igor Lisov suggested that Phobos-Grunt could be sent to orbit the Moon – Earth’s Moon, that is – or may be even an asteroid, if communication is restored at any point before the 13-ton probe re-enters Earth’s atmosphere.
Evolution of Phobos-Grunt’s Orbit
Boosted into space by a Zenit 2 rocket last week, Phobos-Grunt entered into a low parking orbit, where she was supposed to wait only for 2.5 hours before the next booster stage, Fregat, would send her to a higher orbit and then on to Mars. Because the Fregat engine did not ignite, Grunt still orbits just above our heads. “Highly elliptical, with an initial altitude of 347 kilometers at apogee (the high point) and 207 kilometers at perigee (the low point), the orbit initially was predicted to decay by late November, causing the spacecraft to reenter the atmosphere and burn up. But while the apogee has been decreasing (down to 326 km today), the perigee actually has been increasing by about 0.5 kilometers per day (up to 210.2 km today), due to periodic maneuvering by way of the probe’s small thrusters. After it was realized that the first maneuvering episode had improved the orbit, the predicted reentry date was adjusted to mid January, and if the thrusting episodes continue we can expect the date of the probe’s demise to be moved back still more.
An artists concept of the Phobos-Grunt Mission. Credit: Roscosmos
Time for Trajectory to Phobos is Running Out
The improved orbit gives controllers at the Russian Space Agency, Roscosmos, several weeks –even more, if the perigee continues to get higher– to restore communication with Phobos-Grunt, allowing for the uploading of new commands. But, even if control is restored, a flight to Mars and Phobos will not be possible after Monday, November 21st, Lisov explained. Although the Fregat stage is loaded with fuel, to reach Mars, given Grunt’s orbit around Earth and the alignment between Earth and Mars after Monday, would require a higher change in velocity –what propulsion specialists call delta v – than the Fregat is capable of producing.
A Consolation Prize
While cautioning that the idea of sending Phobos-Grunt somewhere other than Phobos falls into the realm of wishful thinking, Lisov urged that efforts to reconnect with the spacecraft continue in full force as long as the craft is in space. Despite several failures of lunar missions, the former Soviet space program did succeed in returning samples from the lunar surface to Earth in the 1970s. Thus, re-purposing the current mission as “Luna-Grunt” or something of that nature is not likely to have the same appeal as Phobos-Grunt has among Russians. Nor could the Grunt landing craft, designed to scoop a surface sample into a capsule that would return to Earth, even set down on the lunar surface. But other components of the science payload might be useful. Though built to observe Mars,China’s Yinghuo-1 orbiter might be able to do something interesting from lunar orbit. Instruments that were to remain on the Phobosian surface might be useful as well.
Then, there is the issue of avoiding reentry. Experts at Roscosmos are confident that the many tons of nitrogen teroxide and hydrazine in Grunt’s fuel tanks will burn up high in the atmosphere if the probe reenters. But people around the planet are scared, and thus might prefer that the fuel be used, even for a one-way mission with undefined science objectives. More importantly, achieving in a partial victory by sending the spacecraft anywhere but back to Earth could give rise to an Apollo 13-like milieu that might reinvigorate the Russian planetary program.
Millions of Tiny Passengers
The Planetary Society’s Living Interplanetary Flight Experiment (LIFE) capsule, on board the Phobos-Grunt spacecraft. Credit:The Planetary Society
As I’ve discussed in a previous update, to be useful scientifically, the Planetary Society’s Living Interplanetary Flight Experiment (LIFE) rides inside the capsule that was designed to return the Phobosian sample to Earth. The point of the experiment is to test the effects of the space environment on several different types of organisms. Because the Moon orbits Earth far outside the Van Allen radiation belts, the radiation received per time by organisms on lunar flights is the same as that received during flights to Mars. If the capsule could be sent into lunar orbit, our millions of passengers would be like organisms traveling inside a meteoroid from Mars. Then perhaps some future mission could recover the capsule some day, and we could study the organisms, as we planned to do upon their return from Phobos.
A Possible Asteroid Mission
Lisov also speculated about sending the Grunt spacecraft to an asteroid instead of the Moon. Various asteroids travel fairly close to Earth, and it’s plausible that a Grunt probe revived after November 21 would have enough delta v to reach one of them. Unlike Earth’s Moon, whose gravity the Grunt lander was not designed to withstand, many asteroids are small. Theoretically, Grunt’s lander could set down on any celestial body with a gravitational force similar to that of Phobos. If any such asteroid candidate exists –and this is a big if– the ascent engine, designed to propel the Grunt return capsule back to Earth might be utilized to deliver a sample of the asteroid, along with the LIFE experiment.
